/*
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE
 * file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file
 * to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the
 * License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */
package org.apache.tuweni.bytes;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkElementIndex;

import java.util.Arrays;

class MutableArrayWrappingBytes extends ArrayWrappingBytes implements MutableBytes {

    MutableArrayWrappingBytes(byte[] bytes) {
        super(bytes);
    }

    MutableArrayWrappingBytes(byte[] bytes, int offset, int length) {
        super(bytes, offset, length);
    }

    @Override
    public void set(int i, byte b) {
        // Check bounds because while the array access would throw, the error message would be
        // confusing
        // for the caller.
        checkElementIndex(i, length);
        bytes[offset + i] = b;
    }

    @Override
    public MutableBytes increment() {
        for (int i = length - 1; i >= offset; --i) {
            if (bytes[i] == (byte) 0xFF) {
                bytes[i] = (byte) 0x00;
            } else {
                ++bytes[i];
                break;
            }
        }
        return this;
    }

    @Override
    public MutableBytes decrement() {
        for (int i = length - 1; i >= offset; --i) {
            if (bytes[i] == (byte) 0x00) {
                bytes[i] = (byte) 0xFF;
            } else {
                --bytes[i];
                break;
            }
        }
        return this;
    }

    @Override
    public MutableBytes mutableSlice(int i, int length) {
        if (i == 0 && length == this.length) return this;
        if (length == 0) return MutableBytes.EMPTY;

        checkElementIndex(i, this.length);
        checkArgument(
                i + length <= this.length,
                "Specified length %s is too large: the value has size %s and has only %s bytes from %s",
                length,
                this.length,
                this.length - i,
                i);
        return length == Bytes32.SIZE
                ? new MutableArrayWrappingBytes32(bytes, offset + i)
                : new MutableArrayWrappingBytes(bytes, offset + i, length);
    }

    @Override
    public void fill(byte b) {
        Arrays.fill(bytes, offset, offset + length, b);
    }

    @Override
    public Bytes copy() {
        return new ArrayWrappingBytes(toArray());
    }

    @Override
    public int hashCode() {
        return computeHashcode();
    }
}
